Make sure to be concise, avoid filler words and meaningless language. Basically say it like it is. Investors don't like founders they can not trust. Be genuine in your pitch and always focus on highlighting the product, not the circumstances that brought it to fruition or your team or anything else. Lead with product, always product.
The deck should tell a story and do it with the most visuals. People are more receptive to visuals over walls of text.
The story should basically state the problem and impact of the problem, how your business solves the problem, and how it would directly benefit the user. Also, make sure to sprinkle your key differentiators in there :)
In premast, we try to provide a wide range of elements that can help entrepreneurs design their pitch decks professionally. I would like to consider your thoughts to include it in our next designs
For us it was visuals that got our investors/partners hooked! Being concise is very important as well. On our deck, we have problem, solution, value proposition, business model, market, competition, roadmap and team. Then we also have a more detailed investor deck that has more information!